Risk Factors at Birth for Permanent Obstetric Brachial Plexus Injury and Associated Osseous Deformities

Table 2

Risk factors and measurements of osseous deformity.

	PHHA*		Version*		SHEAR*		No finger movement at birth
Birth weight	Avg %	𝑃	Avg deg	𝑃	Avg %	𝑃	%	𝑃
>4.5 kg	15±23	0.06	−33±17	0.001	14±16	0.97	65(51–77)	0.82
<4.5 kg	22±21		−26±16		13±11		68(61–74)
Delivery
Instrument^†	23±19	0.45	−27±16	0.79	15±12	0.04	69(59–77)	0.91
Spontaneous	20±22		−27±17		11±11		67(59–74)
Shoulder Dystocia
Yes	20±21	0.61	−28±16	0.25	13±12	0.87	68(62–74)	0.47
No	28±10		−19±6		12±14		50(22–78)

All patients suffered permanent obstetric brachial plexus injury. Averages are given with standard deviation and were compared with Mann Whitney 𝑈-test. Proportions were compared with Fisher’s exact test and provided with 95% confidence intervals.
*PHHA: percent humeral head anterior to the scapular line. Version: degree the glenoid is rotated from normal (retroversion). SHEAR: scapular hypoplasia, elevation, and rotation as measured by percent scapula superior to clavicle.
^†Included forceps, vacuum, or both.